OS2::Process - exports constants for system() call on OS2.


    use OS2::Process;
    $pid = system(P_PM+P_BACKGROUND, "epm.exe");


the builtin function system() under OS/2 allows an optional first argument which denotes the mode of the process. Note that this argument is recognized only if it is strictly numerical.

You can use either one of the process modes:

        P_WAIT (0)      = wait until child terminates (default)
        P_NOWAIT        = do not wait until child terminates
        P_SESSION       = new session
        P_DETACH        = detached
        P_PM            = PM program

and optionally add PM and session option bits:

        P_DEFAULT (0)   = default
        P_MINIMIZE      = minimized
        P_MAXIMIZE      = maximized
        P_FULLSCREEN    = fullscreen (session only)
        P_WINDOWED      = windowed (session only)

        P_FOREGROUND    = foreground (if running in foreground)
        P_BACKGROUND    = background

        P_NOCLOSE       = don't close window on exit (session only)

        P_QUOTE         = quote all arguments
        P_TILDE         = MKS argument passing convention
        P_UNRELATED     = do not kill child when father terminates

Access to process properties

Additionaly, subroutines my_type(), process_entry() and file_type(file), get_title() and set_title(newtitle) are implemented. my_type() returns the type of the current process (one of ``FS'', ``DOS'', ``VIO'', ``PM'', ``DETACH'' and ``UNKNOWN''), or undef on error.


returns the type of the executable file file, or dies on error. The bits 0-2 of the result contain one of the values

Application type is not specified in the executable header.


Application type is not-window-compatible.


Application type is window-compatible.


Application type is window-API.

The remaining bits should be masked with the following values to determine the type of the executable:


Set to 1 if the executable file has been ``bound'' (by the BIND command) as a Family API application. Bits 0, 1, and 2 still apply.

T_DLL (0x10)

Set to 1 if the executable file is a dynamic link library (DLL) module. Bits 0, 1, 2, 3, and 5 will be set to 0.

T_DOS (0x20)

Set to 1 if the executable file is in PC/DOS format. Bits 0, 1, 2, 3, and 4 will be set to 0.

T_PHYSDRV (0x40)

Set to 1 if the executable file is a physical device driver.

T_VIRTDRV (0x80)

Set to 1 if the executable file is a virtual device driver.

T_PROTDLL (0x100)

Set to 1 if the executable file is a protected-memory dynamic link library module.

T_32BIT (0x4000)

Set to 1 for 32-bit executable files.

file_type() may croak with one of the strings "Invalid EXE signature" or "EXE marked invalid" to indicate typical error conditions. If given non-absolute path, will look on PATH, will add extention .exe if no extension is present (add extension . to suppress).


returns a list of the following data:

Title of the process (in the Ctrl-Esc list);

window handle of switch entry of the process (in the Ctrl-Esc list);

window handle of the icon of the process;

process handle of the owner of the entry in Ctrl-Esc list;

process id of the owner of the entry in Ctrl-Esc list;

session id of the owner of the entry in Ctrl-Esc list;

whether visible in Ctrl-Esc list;

whether item cannot be switched to (note that it is not actually grayed in the Ctrl-Esc list));

whether participates in jump sequence;

program type. Possible values are:

     PROG_DEFAULT                       0 
     PROG_FULLSCREEN                    1 
     PROG_WINDOWABLEVIO                 2 
     PROG_PM                            3 
     PROG_VDM                           4 
     PROG_WINDOWEDVDM                   7 

Although there are several other program types for WIN-OS/2 programs, these do not show up in this field. Instead, the PROG_VDM or PROG_WINDOWEDVDM program types are used. For instance, for PROG_31_STDSEAMLESSVDM, PROG_WINDOWEDVDM is used. This is because all the WIN-OS/2 programs run in DOS sessions. For example, if a program is a windowed WIN-OS/2 program, it runs in a PROG_WINDOWEDVDM session. Likewise, if it's a full-screen WIN-OS/2 program, it runs in a PROG_VDM session.


- does not work with some windows (if the title is set from the start). This is a limitation of OS/2, in such a case $^E is set to 372 (type

  help 372

for a funny - and wrong - explanation ;-).


is a shortcut implemented via process_entry().


Andreas Kaiser <>, Ilya Zakharevich <>


spawn*() system calls.


We are painfully aware that these documents may contain incorrect links and misformatted HTML. Such bugs lie in the automatic translation process that automatically created the hundreds and hundreds of separate documents that you find here. Please do not report link or formatting bugs, because we cannot fix per-document problems. The only bug reports that will help us are those that supply working patches to the installhtml or pod2html programs, or to the Pod::HTML module itself, for which I and the entire Perl community will shower you with thanks and praises.

If rather than formatting bugs, you encounter substantive content errors in these documents, such as mistakes in the explanations or code, please use the perlbug utility included with the Perl distribution.

--Tom Christiansen, Perl Documentation Compiler and Editor

Return to the Perl Documentation Index.
Return to the Perl Home Page.